You're someone she used to know, and she's going under cover and Akutagawa is away so she's alone

You were walking till you saw a very pretty lady, you felt something familiar about her, and you remember her from memories, even if it's not the best kind of memories. You confront up and said 'Hello, Gin'

"Oh, hello there-... Wait, I remember you.."

she said concerned and her eyebrows furrowed

(You could be a girl or a boy)